Week 5 Lecture II Flashcards
infrastructure is humanity’s most visible impact on the environment
modern sustainable infrastructure is also essential to minimising human impacts on the environment.
infrastructure challenge in low-income vs high-income countries
In developing economies, providing infrastructure is the key challenge, while in developed countries, maintaining existing infrastructure, which is ageing, is a major challenge
Infrastructure systems
(including energy, transport, water, waste and digital communications) are vital for modern economic activity, but are also major sources of carbon emissions and environmental impacts.
New policies and technologies are therefore needed to enable a transition to more sustainable infrastructure systems
However, these need to take into account the long‐term risks due to increasing infrastructure interdependency, which are not well understood.
infrastructure definition
vs sustainable infrastructure
In this context we consider ‘infrastructure’ to be those assets which comprise the various supply systems for energy, transport, water and waste, while ‘sustainable infrastructure’ is that which contributes towards a future where limited resources are managed responsibly, perhaps through demand management, with minimal impact on the natural surroundings and climate
Economic perspective on infrastructure
In many ways, infrastructure defines the boundaries of national economic productivity. It is often cited as a key ingredient for a nation’s economic competitiveness (Urban Land Institute and Ernst and Young, 2011). The World Economic Forum (WEF), for example, lists infrastructure as the second ‘pillar’ in its Global Competitiveness Index, a measure of national competitiveness
Public investments in infrastructure generally have a positive impact on economic growth, and there is a strong positive relationship between the growth rates of public capital and GDP. All this suggests that significant long‐term investment in infrastructure is a desirable outcome for government and society as a whole.
Whilst such a long‐term approach is attractive in principle, there are significant practical challenges.
For example, risk‐conscious investors could be discouraged from investing in infrastructure associated with a low‐carbon economy (i.e. green infrastructure), since the economic viability of such investments relies heavily on long‐term policies. Policy frameworks such as the UK Climate Change Act (2008) are seeking to deal with such challenges, but as has been the case recently, shorter term disagreements within government about policy priorities can still have a detrimental effect on investment commitments to infrastructure. Further, investments in innovative technologies such as offshore wind are considered higher risk as these infrastructure assets lack a credible investment performance track record in most countries, reflecting that there is considerable learning and rapid technical change occurring, and developers have been historically over‐optimistic about costs and performance. This can often serve to discourage investors in these areas
In more developed countries, infrastructure systems face a number of serious challenges (Hall et al., 2016):
(i) an increased demand for infrastructure services from a growing and ageing population,
(ii) ageing infrastructure assets in need of replacement or rehabilitation,
(iii) risks of infrastructure failure, in particular from climatic extremes and security threats,
(iv) significant investment requirements to counter the vulnerabilities, capacity limitations and supply insecurities associated with an ageing infrastructure system,
(v) the increasing complexity, diversification and interdependence of infrastructure networks, and
(vi) a widespread desire to maintain and improve environmental standards, including decarbonisation across infrastructure sectors.
weakening of the resilience of infrastructure systems
The combined effect of ageing infrastructure, growing demand (nearing capacity limits) from social and economic pressures, interconnectivity and complexity leads to systematic
Climate change
is increasing the risk of extreme events (Field et al., 2012) and hence infrastructure failures.
Overcoming these multiple challenges requires
a long‐term strategic view on infrastructure provision, especially given the long lifespan (many decades or longer) of many physical infrastructure assets (particularly in water, transport and energy), and the long lead time to effect change in these systems
irreversible
Moreover, infrastructure provision can encourage patterns of development and land use that become practically irreversible. Choices about technologies can lock in patterns of behaviour and economic activity’
As part of this modelling activity, we have developed an ensemble of national infrastructure scenarios for Britain that capture exogenous variables that are external to infrastructure systems but nonetheless influence their performance. These include
PICTURE
(i) demographic change, which affects demand for infrastructure services,
(ii) economic change, which affects the demand for infrastructure services, both in final household demand and industrial sectors,
(iii) global fossil‐fuel costs, which affect both operating costs and transport costs in particular (some national policy measures may affect these costs, but these are assumed to be exogenous to the models) and
(iv) environmental change where climate change can affect resources for water and demand for energy. These scenarios are used as direct data inputs for each sector model, ensuring consistent national assumptions
Generally, both gas and electricity energy systems can be structured into the following categories:
(i) fuel sources (coal, gas oil, uranium, etc.) and power generation, (ii) transmission (high‐voltage power network, high‐pressure gas network), (iii) distribution (medium/low‐voltage power network, medium/low‐pressure gas network) and (iv) consumers (electricity/gas demand) (Chaudry et al., 2008)
gas and electricity differences
However, there are differences between these two networks. Natural gas constitutes a primary form of energy that comes from gas fields, while electrical energy is a secondary form of energy, which is formed by the transformation of primary energy (fuel) in a power plant. Gas is transported from the gas fields (suppliers) to customers through pipelines while electricity is transmitted through power circuits. Additionally, gas networks can store natural gas to be used at peak load periods while electricity cannot be stored efficiently or economically (although future electricity storage technologies may emerge).
smart network
It is believed that there is potential to increase overall system efficiency by better matching energy demand and supply through improved data monitoring and information feedback. For example, network operators will get more detailed information about supply and demand improving management of the system such as shifting demand to off‐peak times. As a result, a smart network will be able to better accommodate mass penetration of intermittent renewables and electric vehicles. However, there are many unanswered questions surrounding the system‐wide impacts on the energy system from mass uptake of ICT
Also, alternative demographic projections tend to have the following effects
(i) a larger population tends to increase expenditure by households across the economy,
(ii) a larger population also increases the size of the workforce, permitting higher employment (a higher availability of labour may also curb wage growth) and
(iii) a larger population will also raise demand for government goods and services, and therefore the requirement for necessary infrastructure to support such services.
Video: location matters
Location matters – walking or biking
Better live in an old house with a walkable location rather than a super new huse where you have to frive a car
Video: What was there before?
Field? - negative impact
Replaced or renovating a building? - positive impact
Taking emissions away from the old building
BAD BUILDING – great!!!
net zero –>
net positive
video message
To compensate for the walking distance and for the NEW building you have to build a looot of solar panels to get to net positive –> may be the most expensive and hardest way to get to net positive
video - 4 criteria
4 things: money, walking, technologies, new?, net positive
Envelope
distinguishes the conditioned from the unconditioned area – the boundary between what is conditioned and unconditioned (this boundary is the walls, roof, windows)
if you want smart cities
each house has to be smart
Embodied vs. Operational energies
Embodied vs. Operational energies – old/new buildings
When you renew a building to make it green, operational energy will decrease
‘relation between’
Higher prices
In smaller spaces
cities trap heat
Cities trap a lot of heat cuz of the materials they are built of. There is no nature to suck up the heat. Maybe we need white cities with plants to scale up Albedo?
Green bling
Green bling = technological interventions Alternative model, with 4 criteria Walkability Previous use Envelope Green technologies
video/energy and the built environment (transition theory, efficiency theory, practice theory)
His approach is at level of new configurations Or (re)design-in-context as innovation How could we determine which case it is?
This week
Build on our knowledge of infrastructures and the challenges they
face
• Look at infrastructures at the level of cities, in context of built
environment
• Consider how modelling can inform us on the intersection of cities
and infrastructures
• Introduction to smart cities
• On Monday: in-depth with smart cities
urbanisation
Rapid urbanization
• Since 2007: Over half the population lives in cities
• 2050: 66% is predicted to live in cities
Are cities important for the climate?
According to IPPC (2014):
• Cities have a key role in tackling climate (Van
Staden 2014, Climate Change Implications for
cities)
• Urban areas account for 67–76% of global final
energy consumption
• Urban areas account for 71–76% of fossil fuel- related CO2 emissions
• City as having appropriate scale
• (not faceless, accountable)
Why are cities important for energy?
+ or -?
Densely populated (demand)
• Centres of production (demand)
• Centres of innovation (sustainability)
• Densely built (sustainability) regulation, building
standards, targets for building, planning guidelines,
passive design, certification schemes
• Physically distinct (urban heat islands) (demand and
sustainability)
Urban energy demand?
What are energy consumption patterns in urban areas?
Main contributors:
• Buildings
• Transport
Energy consumption of both buildings and transport is highly interdependent
• Urban spatial layout (=urban form) influences mobility needs
• Energy demand for heating and cooling: depends on behavioral factors, building
design, and climate
Three major dimensions of urban
energy (embodied vs organisational energy)
Embodied energy used for extracting and processing of raw materials, manufacturing of construction materials,
transportation and distribution, and assembly and construction
Cradle-to-gate/ cradle-to-site/ cradle-to-grave (inc. demolition & recycling)
Operational energy used during the occupancy stage of a building (AND appliances) during its entire life cycle
space and water heating, space cooling, lighting, running the elevators, etc
Transport
From this unit, be able to answer:
If a building is largely built using recycled material…?
What would the ratio of embodied: operational energy tell you?
How does this relate to the TedTalk on Green buildings are more than brick and mortar?
Not only scale,
but
urban forms also matter
picture on the slides
Not only rate of urbanization matters for energy
consumption àurban form (1)
urban form is the physical characteristics that make up built-up areas
• includes the shape, size, density and configuration of settlements
• can be at different scales: from regional, to urban, neighbourhood, ‘block’
and street
From Urban form and infrastructure: a morphological review
(a foresight report)
Not only rate of urbanization matters for energy
consumption àurban form (2)
Urban form significantly affects both direct (operational) and indirect (embodied)
energy
• Urban form affects well-being and is associated with economic productivity
• Urban forms affects energy used for transportation:
• Bus=1
• Train=2x
• Private car=4x
density and transport energy graph
explain graph
Urban form: dispersed vs compact
• Urban density affects projected energy use as much as efficiency
measures
• Urbanization predicted to grow
• …BUT population densities are projected to continue decreasing through
2050 in South Asia, Europe, and North America
• What will this mean for urban form?
• These trends suggest that the dispersed urban forms in these regions will
continue to dominate urban expansion patterns towards 2050
Relation between density and energy use
- As urban population density increases, the dwelling size decreases
- floor area per capita (FAC) tends to decrease
- Smaller dwelling size= lower per capita energy use
- Lower heating and cooling (if pop does not grow)
- Density makes it possible to implement more efficient technologies:
- district heating
- district cooling (more novel)
But is denser always
better?
Yes and No • trade-offs • higher urban densities =disproportionately larger embodied energy in buildings and other infrastructure • higher exposure to air pollutants • traffic congestion
USA vs Spain (two cities)
slide picture
How can you know what is ‘better’?
Calculating embodied and operational energy
Estimating the energy consumption of buildings is a complicated
process
Even more complex at neighborhood or city level
At present there is no unique, best, approach to the problem.
A common approach is setting up a model to represent the real world’s
complexity and obtain a better understanding of its dynamics
Numerous models across disciplines
Models, not measurements!
Envelope (picture)
explain picture
Climate and built environment (1)
a second application of modelling
• How to assess climate/built environment interactions?
• Modeling of temperature
• according to expected temperatures (diff. scenarios; heat
waves)
• for different type of housing
• for different types of users (at home all day, away at
school/work)
• simulating different adaptations (retrofit, intervention on
‘envelope’ like shutters; behaviors like not opening windows)
Different dwellings
4 on the slide
Climate and built environment (2)
• How to implement policy?
- Building standards
- Planning guidelines
- Certification schemes (BREEAM, LEED)
Calculating transport
• Also, complex • Heterogeneous (mobility/transport/transit, etc) (meaning of moving) • Combinations of travel modes • use of models is a common approach • used to estimate and forecast future fuel consumption, transportation’s GHG emissions • study travel behavior (more on this next week)
The ‘compact city’ as ideal?
Critiqued for feasibility and benefits
• Alternatives:
• polycentric cities
• Smart growth (prevent sprawl, think about transp. infra)
• Eco-towns, sustainable communities (environmental technologies, reduce car use, and provide good quality
of life and amenities)
• Self-reliant (bio-regional)cities (live within own limits)
• Smart cities (make systems work together more efficiently and manage the city more effectively)
Smart Cities
Diversity in meaning and implementation
• Framing rather than concept or even brand
• Loosely and imprecisely but frequently related to sustainable cities
With regards to energy:
• Often implemented on district scale (‘neighbourhood’)
• Road to sustainability can be through integration
• Recall the walk scores as a feature of buildings
EU’s definition
Smart cities stimulate
• Energy sustainability
• Mobility
• New business models and public-private partnerships
• Advanced use of big data (and by implications, sensors, networks, comm infra)
On Monday: Smart Cities and Communities
